Substrate and atmosphere influence on oxygen p-doped graphene

作者：Piazza Aurora; Giannazzo Filippo; Buscarino Gianpiero; Fisichella Gabriele; La Magna Antonino; Roccaforte Fabrizio; Cannas Marco; Gelardi Franco Mario; Pignataro Bruno; Scopelliti Michelangelo; Agnello Simonpietro^*

来源：Carbon, 2016, 107: 696-704.

DOI：10.1016/j.carbon.2016.06.077

The mechanisms responsible for p-type doping of substrate supported monolayer graphene (Gr) by thermal treatments in oxygen ambient have been investigated by micro-Raman spectroscopy, atomic force microscopy (AFM) and X-ray Photoelectron Spectroscopy (XPS), considering commonly employed dielectric substrates, such as SiO2 and Al2O3 thin films grown on Si. While a high p-type doping (similar to 10(13) cm(-2)) is observed for Gr on SiO2, no significant doping is found for Gr samples on the Al2O3 substrate, suggesting a key role of the Gr/SiO2 interface states in the trapping of oxygen responsible for the Gr p-type doping. Furthermore, we investigated the doping stability of Gr on SiO2 during subsequent thermal treatments in nitrogen (N-2), carbon dioxide (CO2), water (H2O) or in vacuum controlled atmospheres. These processes induce only minor effects on the doping of Gr but for H2O and principally affect its defectiveness, suggesting that the literature reported air influence on the doping depends on water present in the atmosphere.

• 出版日期2016-10